Cummins ECM CM2450 Insulation harness

Jaltest JDCM850 - Cummins ECM CM850 Insulation Harness

The JDCM850 (Cojali part number 78901064) is the Cummins CM850 ECM insulation harness required for the Jaltest Central Services Cummins Revision Update procedure. The CM850 ECM is the earlier-generation Cummins control module found in ISX engines from the pre-DPF and early DPF era. Shops servicing these older ISX engines and wanting to perform ECM calibration updates through Jaltest Central Services need this specific harness.

What the Cummins Revision Update Does

The Jaltest Central Services Cummins Revision Update (part #70810000, $250.00 per action) allows shops to perform OEM-level Cummins ECM calibration updates with Cojali remote technician support. The JDCM850 harness is placed on the CM850 ECM during the update. Process:

1. Verify initial conditions through Jaltest software
2. Request the Central Services action via Cojali USA or your distributor
3. Payment processed
4. Schedule — Cojali customer support performs the update remotely

Harness Specifications

• SKU: JDCM850
• Cojali Part Number: 78901064
• Application: Cummins ECM CM850 — early ISX engines
• Function: Insulation harness for ECM update procedure
• Required For: Jaltest Central Services Cummins Revision Update (action #70810000)
• Also Requires: Active Jaltest CV license and Jaltest Link V9
• MSRP: $285.00

Free Central Services Action With Purchase

Per the 2025 Jaltest Pricelist: purchasing the JDCM850 includes one free Cummins Central Services Revision Update action (valued at $250.00 — Detroit Diesel actions excluded). This is a meaningful benefit — your first ECM update is effectively covered by the harness purchase.

Cummins ECM Platform Reference

• JDCM850 (78901064, $285) — Cummins ECM CM850 — older ISX engines (pre-DPF / early DPF era)
• JDCM2150 (78901065, $285) — Cummins ECM CM2150
• JDCM217.9 (78901067, $285) — Cummins ECM CM2250
• JDCM2250 (78901066, $285) — Cummins ECM CM2350 / CM2450

Shops with a mixed fleet of old and new Cummins engines may need multiple harnesses. Call us if you need help matching your engine to the correct harness.

Who Needs This Harness

Truck shops and fleets servicing older Cummins ISX engines with CM850 ECMs who want in-house ECM calibration update capability through Jaltest Central Services.

Why Buy From OEM Diagnostic Tools?

OEM Diagnostic Tools has specialized in professional diagnostic equipment since 2016. We carry all four Cummins ECM harnesses, ship free on every order, and provide free tech support at 866-217-0063. Call us before ordering if you need help identifying your engine ECM. Full warranty on every purchase.

Call 866-217-0063 for quick answers and help!